Abstract:
A few days were spent in the Miers Valley to collect samples of gypsum for geochemical analyses. Surprisingly carbonate "biscuit" similar to that found in the Taylor Valley were found. Thus, we noted the elevations of carbonate and gypsum, also in relation to ancient lake levels and moraines. Samples were subjected to geochemical analyses. Kenyte-like boulders in the terrace sequence had been ... depositied in a tuffaceious matrix. Apparently the boulders had been deposited on the subaqueous part of the delta at a time of higher lake level.The feldspar crystals in these boulders were dated with K-Ar as well as having the glass in the tuffaceous matrix fission-track dated. With dating, we should be able to tie in the age, form and evolution of the old lake levels, deltas and moraines of the Miers Valley with the Taylor Valley. Further samples were collected the following season for dating the formation of the major landforms, especially the moraines and lake levels in the Miers Valley. The Marshall Valley was visited and a massive gypsum vein was sampled and dated. The Walcott Bay was surveyed but no carbonate was found and the shoreline of Mt Discovery was surveyed for carbonates.